There are not many direct studies of DNMT inhibitors purely as radiosensitizers in GBM, but some clues exist: a general study in cancer cell lines found that pretreatment with DNMT inhibitors enhanced radiosensitivity in a variety of cells by promoting more apoptosis and less cell cycle arrest after radiation (Kang et al., 2019). This evidence concerns the gene DNMT1 and glioblastoma.